I was just about to out my rear window in last week and I noticed that the rear seal from autokratfers had some slack in it. From what I remember I ordered the 2dr seal and not the 4dr, I have tried pulling it around the glass but you can still feel a bit of slack in the seal on the bottom corners. Is there supposed to be some slack in it when you put it on the glass? I would hate to install it all the way and then have to take the glass back out again. Its not huge amount of slack, just enough so that I can wiggle the gasket back and forth on the bottom corners, I always thought It was supposed to fit tight, and yes I do have the gasket taped to the window.
IIRC mine was a bit loose feeling also, once I installed it and the butyl was applied to the corners and across the bottom I felt it would be fine, and it has been.
Mine was the same, i almost felt like i should have cut a few inches out of it to be honest (was a long debate in my head....but once i butyl'd it and layed it on the car i seen it sat A LOT better & once it was roped around it was perfectly fine, no leaks & i washed it prob 15 times since that.